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Steel spur gear pros/cons

This is my 3rd nitro. 1st revo, 2nd hpi savage x4.6, and now slayer pro. The first 2 I used steel spurs on. The revo it worked fine, the savage snapped a rod after 6 tanks of fuel. I haven't put one on my slayer yet, so I would like to know if it is worth it or not.

No need, the only resons why spur gears strip is either the mesh is not consistent due to loose screws, mounts, poor alignment of the motor mount or tranny, bad CB bearings, having the throttle nailed too hard when landing....

I've seen tons of BB's using plastic spur gears with no problems for years..... You want that gear to be plastic IMHO...

I understand Keeping a good mesh is needed whether I use plastic or steel. And adding a strong part transfers weakness to the next. I'm trying to take out all the weak points, ie... Plastic. I'm starting from the inside and working my way out, going with all steel and aluminum. Yes I know aluminum is heavy. I'm not racer, added weight is not going to effect my fun factor. So please no plastics vs aluminum debates. What my question is, will the engine be effected by doing the steel spur/clutch bell combo? The other parts of the truck are going to be steel, but the last thing I want is to damage my engine, or take away reliability?

Not sure if I should answer as you haven't listened to the others. You'll have more rotating mass to deal with in steel. And again, the spur gear is designed to be the weak point otherwise any shock to the drivetrain will be taken out someplace else.

I understand Keeping a good mesh is needed whether I use plastic or steel. And adding a strong part transfers weakness to the next. I'm trying to take out all the weak points, ie... Plastic. I'm starting from the inside and working my way out, going with all steel and aluminum. Yes I know aluminum is heavy. I'm not racer, added weight is not going to effect my fun factor. So please no plastics vs aluminum debates. What my question is, will the engine be effected by doing the steel spur/clutch bell combo? The other parts of the truck are going to be steel, but the last thing I want is to damage my engine, or take away reliability?

And what I'm saying is your Spur gear isn't the weak point..... Big Blocks can run plastic spurs no problems, not having the plastic spur will only cover up problems that a stripping spur would cause you to detect, investigate before you end up buying a new set of diffs or tranny gears....

I'd go with driveshafts, and if you aren't going to a BB motor, going to steel gears is just going to cost money and slow you down. Again with the rotational mass thing....

I've a tranny that went 20 gallons of all out racing and never failed. ALL plastic. And funny,,, I haven't stripped a spur gear in years. OH and I have 4 ground RC's 2 of them racers.....

But if your heart is set on it, just make sure that slipper doesn't fail or you WILL be buying new driveline parts...

And remember you need a hardened steel CB to match with that spur gear. Metal spurs are made from hardened steel and will eat stock CB's for breakfast in a short time...

You would be better off with RPM arms and skids, Ti turnbuckles, things like that. Drop the EZ start and get it light with a pull start, less weight = less force when in a crash = less damage...

Well ive never seen anyone have any problems with steel spur/clutch bell combo. So if you take offense to my question, thats not my intention.Most people are biased when it comes plastic or steel.So if theres anyone that has an all steel drivline, feel free to comment. Can these nitro engines handle the added weight and rotational mass??

Also the spur and cb is the weakest point IMO , because its exposed. My mesh is perfect until a small rock or dirt get caught and throw my alignment off. And 10 $5 parts=$50. So in the end I would be saving money with steel.

Robinson racing sells a hardend cb/spur combo. One of the guys at my lhs runs them in his picco BB and had nothing but good things to say. If your wanting a steel set up that's the only option. I've watched my friend wreck cb after cb when his mesh was off just alittle. He was just running a steel spur with a stock cb.

I'm all about advice, that's why I'm here. But to say that the spur and clutch bell are not weak points is crazy. What's the first thing that went out on you ( besides servos ) with nitro rc? This is the only problem I run into, and I feel like it should be the first thing that is taken into consideration. I appreciate everyone's knowledge, and am currently running a plastic spur. P

i have run the stock plastic on 2 nitro's for over a year and have had 0 issues. I run my nitro's hard in all kinds of crap including mud and loose gravel. You can take the advice given to you in any way its just advice. If you want to run steal then by all means do it.. Like i said earlier you have to keep a week part in their some ware as a $5 part is way cheaper to replace than a engine or 2 is. if it is stones taking out your spir why not make a sheild to keep the stones out of their..

Well I got the slayer pro out for a run. All I have to say is wow, and thank you traxxas for letting me enjoy nitro again. 2 hrs of extreme running, and not a single issue. Truck ran flawlessly. I had some bad high speed crashes, were I was sure I was done for the day, but nope. I always had issues with my last 2 nitros. Revo 3.3 (because I was new to rc and had no clue what I was doing), and hpi savagex4.6(junk from bumper to bumper). I have no plans on running any steel now. Thanks for all the information.

OH and it's hardened steel again hardened steel you would need. Stock CB's are not hardened steel and the hardened steel spur will eat those up... IF your heart is still set on spending that much money when all you are doing is masking the symptom and not finding the problem. The spur being plastic, is not the real problem...

Stripped Spurs are a symptom of the problem or problems (maybe more than 1).

OH and it's hardened steel again hardened steel you would need. Stock CB's are not hardened steel and the hardened steel spur will eat those up... IF your heart is still set on spending that much money when all you are doing is masking the symptom and not finding the problem. The spur being plastic, is not the real problem...

Stripped Spurs are a symptom of the problem or problems (maybe more than 1).

This is an issue I am struggling with right now. I just stripped a spur gear and I want to make sure I am not making any mistakes before I go out for the next test drive. I agree with the argument that you should only use plastic spur gears mainly so this can act as your weak point for the rest of the more expensive drive train components but I have a question before I proceed.

When I bought my used slayer, it had a spare bell/gear that was smaller than the one currently mounted. The stripped gear was a 36t gear. The guy I bought it from also said he upgraded the gear to make it faster. Well, I since I found out the stock spur gear is a 36t, he must have been talking about the gear on the bell, does this sound right?

So when I went to buy a new gear, I decided to buy both a 36t and a 38t so I could have two different options based on the tires I use and terrain I plan on driving on. I noticed the new 38t gear I bought was larger and when I tried to mount the 38t gear to the current larger bell/gear that was mounted, the fit seemed a little tight, so I took that one off and mounted the smaller spare gear and it seemed to be a better fit. My questions are, how many combinations of bell/gear and spur gear are there? And how do I make sure I have the right combination? Or are all combinations compatible and you just have to adjust the engine mount to the proper “Mesh”?

My questions are, how many combinations of bell/gear and spur gear are there? And how do I make sure I have the right combination? Or are all combinations compatible and you just have to adjust the engine mount to the proper “Mesh”?

As long as the pitch of the gears is the same any combination would be compatible if there is enough adjustment in the mount for the gearing. You just have to adjust the engine mount for the different tooth counts/ratios.
The mesh between the gears should be as tight as possible with just a little play/lash between the teeth.

Thanks, I was reading in the manual that you adjust the mesh with a standard piece of paper but I wasn't sure if all bell gear, spur gear combinations were compatible. If I remember right, the pitches matched up but I will double check.